Contribution of asphyxia to the induction of hearing impairment in jaundiced Gunn rats.

OBJECTIVES

This study was designed to determine whether asphyxia contributes to the induction of hearing impairment during neonatal jaundice.

METHODS

Asphyxia was induced in jaundiced and nonjaundiced Gunn rats on postnatal days 1 (low bilirubin levels) and 10 (elevated bilirubin levels). Auditory nerve-brainstem evoked response thresholds were assessed in 21- and 28-day and 3-month-old rats.

RESULTS

Asphyxia by itself or jaundice by itself did not lead to any type of hearing impairment. However, the combination of both high plasma bilirubin levels and asphyxia in 10-day-old rats but not in 1-day-old rats was accompanied by a progressive hearing loss in these rats.

CONCLUSIONS

The contributory effect of asphyxia on neonatal jaundice may have important clinical relevance if asphyxia, for example, respiratory distress, accompanies neonatal jaundice.